Formation Instability

When dealing with areas of formation instability it is necessary to:

- trip cautiously through swelling formations

- pick up and ream midway through each stand (if hole conditions are severe, more…

Changing a Bottom Hole Assembly

To avoid problems with under gauge hole and BHA changes it is important to ensure the following to reduce the riskof stuck pipe:

  • bits and stabilisers shall always be gauged after each trip
  • if the bit…

Pipe Sticking

In many drilling operations, the drill string is stuck while pulling out after first having experienced tight hole, swabbing and overpulls.

This indicates the following shortcomings:

  • Pulling out has…

Stuck Pipe Prevention

Good drilling practices, particularly with regard to circulating and tripping activities, can greatly reduce the occurrence of stuck pip.

Stuck Pipe Procedures

Drilling Contractor personnel must be…

Overpulls/ Stuck Pipe In Surface Hole

If any tight hole is experienced when drilling with water the followint actions should be taken to prevent stuck pipe:

- With kelly: Immediately pull the string back to above the tight spot (after…

Preventing Differential Sticking

The Drilling Programme shall indicate any permeable formations which may lead to differential sticking, particularly if the risk of differential sticking is considered to be high.

Data Acquisition


Hole Cleaning

The following are possible indicators of hole cleaning problems:

  • excessive overpull on connections and trips
  • reduced overpull when pumping
  • excessive fill after trips
  • erratic and increasing torque…

Use of Drag charts for hole cleaning - WellPlan

Softwares are used to produce Drag charts on which is shown the measured and predicted weights vs. depth. The purpose is to provide the crew with the expected torque and drag during the drilling of…